Natamycin (also known as pimaricin or tenecetin) is a well known antibiotic (Florey, "Analytical Profiles of Drug Substances", Vol. 10, 1981; Merck Index, 8th ed., "Pimaricin", p. 834). Although its valuable antibiotic properties have been recognized, there has been little research or commercialization of natamycin because of the extremely high cost of its manufacture. Because of its solubility in various liquids, natamycin recovery processes have not been economic. A need exists for an economic natamycin recovery process.
Natamycin has been prepared by fermentation, such as disclosed in U.K. Patent 846,933 using Streptomyces gilvosporeus. In this process, natamycin is recovered by methanol extraction followed by tedious steps of adsorption and elution. Penick, U.S. Pat. No. 3,378,441, discloses recovery of natamycin by salting it out of the fermentation broth, extracting with methanol, removing the solids, and then evaporating the liquid. Struyk, U.S. Pat. No. 3,892,850, discloses recovery of natamycin by extraction with acidified butanol followed by distillation and precipitation. Struyk also discloses calcium chloride dissolved in methanol to improve natamycin solubility. Each of these processes require an expensive recovery step, such as adsorption and elution, distillation, or evaporation. U.K. Patent No. 844,289 shows the precipitation of natamycin from acetic acid by the addition of water.